Quiddity and Quid Pro Quo
I just read a cool line of poetry that made me look up some words/phrases which I already knew in Latin, but which threw me for a metaphysical loop when I read them together.
quiddity n: the real nature or essence of something which makes it different from others
Etymology: Latin quid 'something' + -ity
Webster's New Millennium™ Dictionary of English, Preview Edition (v 0.9.7)Copyright © 2003-2008 Lexico Publishing Group, LLC
quid pro quo n: 1. (italics) Latin. one thing in return for another. 2. something that is given or taken in return for something else; substitute. [Origin: 1555-65; L quid prō quō lit., something for something; see what, pro]
Dictionary.com Unabridged (v 1.1) Based on the Random House Unabridged Dictionary, © Random House, Inc. 2006.
"and the quiddity fades into the quid pro quo"
~ from "Unapproved Road" by Paul Muldoon in Moy Sand And Gravel